The mixing time, the temperature and the degree of dilution of olive paste are the main parameters liable to change during mixing and oil ext raction. They can greatly differ from a processing run to another, with variations being observed in Tuscan oil mills, between 26ºC and 36ºC, 40’ and 90’, and 10% and 50% respectively, for the temperature, the mixing time and the water added during the centrifugal extraction. This note reports on the results of some experimental trials run during the 1998 olive oil year in Tuscany. The mixing time and temperature as well as the olive paste dilution were changed one at a time and were assessed for their influence on extraction yield and oil quality. The best conditions to optimise the product yield and quality were identified.